AC/DC/DCC model train on board sound module with wireless control

ABSTRACT

A method, apparatus and system for AC or DC track powered model trains which increases the number of remote control functions available to the powered engines via an on-board sound decoder module. The functions include sound functions, including bell, whistle, brakes, announcements, and the like, and any other functions programmed into the on-board sound decoder module. The invention is compatible with traditional AC, DC, and DCC systems and allows the hobbyist to use a wireless controller to operate the engines and associated functions in a remote fashion.

BACKGROUND OF THE DISCLOSURE

This disclosure pertains to the field of control systems for modeltrains, and specifically to an improvement which provides an easy-to-useand affordable system which expands the number of “on board” featuresavailable, including, but not limited to, sounds, lights, and braking.

For many years, model railroaders have desired an affordable andeasy-to-use life-like model train. Early Lionel AC model trains (drivenby an AC motor) were powered by an AC power pack or power supply. Thepower pack fed AC power to the track and the model train picked up thepower by its wheels and a center feed shoe to provide the AC power tothe motor. The engine speed was controlled by the amplitude of the ACvoltage on the track that was varied by the user operating the leversassociated with the power pack. At a later time, Lionel introduced aninnovative electrical-mechanical on-board motor control unit thatallowed the hobbyist to change the engine's direction by simplyinterrupting the AC track power. This unit was later improved by addinga neutral state to allow the train to stand idle when the track voltagewas applied. This feature allowed the engine's headlight or sound tostay on while the engine was stationary. Each time the AC power wasinterrupted, this motor control unit had a state sequence that movedfrom neutral to forward, forward to neutral, neutral to reverse, andreverse to neutral. This motor control unit is often referred to as areverse unit or “E” unit, and consisted of a solenoid device. Later,Lionel added DC voltage to the AC track to trigger the on-board whistle.A further improvement was to use positive DC to activate the whistle andnegative DC to turn on or off the train's bell.

Most early trains were powered by AC motors as a cheap, reliable DCmotor was not yet available. With improvements in motor technology,small DC “can” motors were made available for use in the model trainengines, having such improvements in slow speed and braking and greatlyreduced “lugging” or stuttering when operating the engines at slowspeed. With the addition of the DC “can” motors, the operative functionsof the model trains were made to appear more realistic. Also, DC powerpacks were easier to manufacture for the increase power demands, withbetter power regulation. A DC power pack has a variable DC outputcontrolled by a user-operated lever or the like, with a double-poledouble-throw (DPDT) switch to change the polarity of the DC output. TheDC model train's motor is directly connected to the pickup wheels andcenter shoe so the engine's speed is proportional to the DC trackvoltage. To change the engine's direction, the user simply flips theDPDT switch on the power pack to change the track's power polarity. Onlyone engine can be operated on the track insofar as the voltage is thesame for the entire track, thus multiple engines on the same trackcannot operate independently. Multiple blocks of track, eachindependently powered by individual power packs must be used toindependently operate multiple engines with different directions anddifferent speeds. This is referred to as “block switching” in the modeltrain community, and has been a staple of multiple train operationduring the “Golden Era”.

In recent years, a number of electronic control systems have beendeveloped that attempt to solve the problems of independent traincontrol and expand remote control ability. One approach is calleddigital command control, or DCC. It uses a command station to send ACpulses onto the track where the train receives the pulses via the wheelsand pickup shoe. A receiver or decoder is installed in the engine todecode the pulses and provide for the various operations that the pulseswould be indicative of. The decoder includes a full wave bridgerectifier to convert the AC pulses to DC to provide the engine'snecessary drive power, and then decodes the pulse width modulation (PWM)signals to provide the control signals that are used to determine theengine's speed and direction, as well as any additional commands, suchas the various sounds and the like. Since the motor is no longerdirectly connected to the track, the changing polarity of the track willnot change the engine's direction. The engine's speed and directioncommand, as well as any additional commands and control, can be beencoded into the AC pulse packet. By changing the track voltage polarityand timing the duration of each polarity change, many states or signalscan be encoded to control the engine. The current NMRA (National ModelRailroaders Association) DCC protocol defines a 56 us (microsecond) ACpulse as a “1” and a 122 us pulse as a “0”. Thus, just as in any serialcommunication protocol, a combination of“1”s and “0”s can be used toform any digital command signal. The command station transmits a seriesof digital command packets onto the track which feeds the engine. A DCCpacket contains a header, address field, data field, and error detectionfield. By assigning different addresses in the decoders associated witheach individual model train engine, multiple engines can be controlledon a single track by addressing each engine individually and setting thespeed and direction.

DCC provides the most realistic model train operation was a great stepforward for modern model railroading. However, the model train communityis made up in large part by hobbyists from the “Golden Era” who stillprefer to use conventional DC power packs to control their engines,avoiding the use of digital command control because they either find thedigital command control system is too complicated or because they preferto operate the model trains with equipment from their youth. Somedigital command control systems can seem overwhelming to thetraditionalist, with a manual having many pages relating to variouscontrol schemes; therefore using a traditional DC power pack to controlthe on-board module is still the first choice of many hobbyists.

U.S. Pat. Nos. 4,914,431, 5,448,142, and 5,184,048 to Severson et al,introduce the concept of changing DC track polarity and timing theduration to generate signals in order to control an on-board unit. Theon-board sound modules based on this concept use the DPDT switch on thepower pack to generate a control signal. The engine's speed command isin proportion to the amplitude of the track voltage, with the engine'sdirection controlled by the initial track voltage polarity. A fastdouble change polarity is used to turn the engine's bell on or off. Asingle change of the polarity turns the whistle on, with another changeback signal turns off the whistle. This on-board sound system cancontrol the engine's direction, speed, and two extra remote functions,mainly whistle and bell, and is compatible with existing DC power packs.

The system disclosed by Severson et al. has the certain limitations.First, there is a significant delay in the blowing of the whistle. Whenthe direction switch is toggled, the on-board sound unit has to wait fora period of time to make sure that it is not a double change of the DCtrack voltage polarity before it activates the whistle. Second, it isvery hard to control the duration of the whistle. When the trackpolarity is changed to cease blowing the whistle, the sound unit has towait for another period of time to make sure that it is not a doublechange of the track polarity. Third, the system only generates twostates to control the on-board sound unit; thus there is no way togenerate more than two states by the toggling of the DPDT switch.Fourth, the constant need to toggle the DPDT switch is bothersome. Theuser's fingers can become sore from the action of operating the switch.To make the unit more user-friendly, a push button and relay circuit hasbeen introduced to replace the flipping of the DPDT switch; however,this adds to the cost of the unit.

U.S. Pat. Nos. 5,251,856, 5,441,223, and 5,749,547 issued to Young etal., disclose providing a digital message, which may include a command,to a model train using various techniques. The digital message(s) aretypically read by a decoder mounted in the train, which then executesthe decoded command. A remote control unit transmits radio frequency,infrared, or other signals to a base unit. The base unit combines afrequency shift key (FSK) signal with the power signal applied to thetrack to send an address and data signal to the powered block section ofthe track. The addressed train on that power block section will receiveand decode the signal. The Young system does not send the signaldirectly to the on-board sound module.

To overcome the above limitations and reduce the cost, the presentdisclosure introduces a low cost, five function wireless transmitter andreceiver chip set to generate control signals to the on-board soundmodule. Instead of using a DPDT switch to change the polarity of thetrack voltage to generate limited signals, the receiver chip sends 5-bitdigital signals to the I/O port of the microcontroller of the on-boardsound unit. The five-function wireless chip set can generate 5-bitbinary code to input to the microcontroller on the on-board sound unit.This means that a low cost wireless solution can be used to activate upto 32 remote functions to control the on-board sound unit. That isenough to activate all the necessary on-board sounds and other functionsand make model railroading more life-like.

SUMMARY OF THE DISCLOSURE

In accordance with the present disclosure a control system has beendeveloped for and AC or DC powered model train system which uses anon-board sound module to control the model engine's sound and otheron-board features. On-board means that it is integrated into a remoteobject (a minature model locomotive in this case) that is addressed bythe remote control signals. The object is to increase the number ofremote control functions to meet the ever increasing availability anddesireability of “on-board” features, such as head light, tail light,Mars lights, whistle, air horn, bell, air release, brake, emergencystop, announcements, etc. This control system is compatible withtraditional power packs, sending the control signals wirelessly ratherthan through the power on the track. Using the wireless controller, thehobbyist will also be able to walk around his layout to operate hisengines unencumbered.

DESCRIPTION OF THE FIGURES

FIG. 1 is a pictoral view of the system:

FIG. 2 is a general schematic of the system:

FIG. 3 is a schematic of the system with a model train under DCCcontrol:

FIG. 4 is a schematic of the system with an AC powered model traindriven by a DC motor;

FIG. 5 is a schematic of the system associated with a DC powered modeltrain;

FIG. 6 is a pictoral view of the wireless remote control device.

DETAILED DESCRIPTION OF THE DISCLOSURE

The control system can be implemented for DC model trains and some ACmodel trains driven by DC motors. FIG. 1 is a pictorial view of thewireless system.

FIG. 2 is a schematic of the most general case. Block 205 represents thewireless transmitter. Block 204 represents the function receiver. Block202 is a full bridge rectifier with filter. The rectifier converts thetrack power to DC to power the PWM circuit and microcontroller (MCU), aswell as provide power to the model train's motor. Block 203 is atwo-channel analog-to-digital converter, A/D. Block 200 is a MCU. TheMCU is used to measure the voltage of both rails of the track and theirwaveform. By monitoring both rails of the track waveform, the MCU canidentify the type of track power. Block 201 represents the PWM. The DCmotor which drives the engine is represented by 206.

As shown in FIG. 3, if the MCU 300 detects a DCC track signal, it startsthe DCC operation. The on-board sound module will act as a regular DCCsound decoder. The MCU 300 will receive the DCC command control packetto decode the command and control the engine's speed and direction byPWM block 301. It will also receive accessory commands to controlon-board sounds accordingly. Since some DCC systems on the market do nothave enough accessory functions to control the on-board sound, the MCU300 will also activate the wireless function to control those additionalfunctions and sounds not covered by the DCC system, effectively all ofthe sounds and functions that are stored in the flash memory chip indigital form.

If the MCU does not detect a DCC track signal, it will try to determinewhether the track is AC powered or DC powered. If it finds the powertrack is AC, as shown in FIG.4, the MCU 400 will automaticallycompensate the DC offset to get the correct speed command while the userpresses the Bell or Horn button on the AC pack 407. During AC operationthe control unit will automatically set from neutral to forward, forwardto neutral, neutral to reverse, and reverse to neutral sequentially whenit detects an interruption of track power. The amplitude of the ACvoltage on the track controls the speed of the AC model train. When theAC track voltage is less than 5 VAC, the MCU 400 will not output the PWM401 to the DC motor; therefore the engine will not move, but insteadwill sit idle with the engine idle sound operating. When the AC trackvoltage is greater than 5 VAC, the MCU 400 will output the PWM 401 tothe DC motor and generate the engine sounds associated with the slowmovement, the engine starting to move and make the sounds associatedwith a slowly moving train. When the user presses the whistle or othersound key on the wireless transmitter 406, the transmitter will transmita 5-bit binary code to the receiver. The receiver will pass the code tothe MCU and the MCU will activate the whistle or other sounds. Thehobbyist can thus use the AC power pack to control the model train speedand direction in the traditional ways and use the wireless transmitterto activate the on-board sounds and functions.

If the MCU does not detect a DCC track signal or AC voltage on thepowered track, it determines that the track is powered by a DC powerpack 507. FIG. 5 shows a schematic of this case. When the DC trackvoltage is less than 5V, the MCU 500 will not output the PWM 501 to theDC motor, consequently the engine will not move. It will sit idle withthe idle engine sound. When the track voltage is greater than 5 V, theMCU 500 will output the PWM 501 to the DC motor and generate the enginesounds associated with the engine starting to move and the slow movingsound generated. By detecting the polarity of the track MCU 500 controlsthe PWM 501 and accordingly controls the engine's direction. When theuser presses the whistle or other sound key on the wireless transmitter505, the transmitter will transmit a 5-bit binary code to the receiver504. The receiver 504 will pass the code to the MCU 500 and the MCU willactivate the whistle or other sounds. The hobbyist can thus use the DCpower pack 507 to control the model train speed and direction in thetraditional ways and uses the wireless transmitter to activate theon-board sounds and functions.

A program executed on a computer and associated with the on-board soundmodule causes the computer to perform the steps of receiving anddecoding the digital control signal to control the on-board trainfunctions, such as various sounds and lighting functions.

While presently preferred embodiments have been described above, variousother modifications and adaptations of the instant invention can be madeby those persons skilled in the art without departing from either thespirit of the invention or the scope of the appended claims.

1. An apparatus for providing a new control capability for DC modeltrains and for AC model trains driven by DC motors, said apparatuscomprising: a) a wireless transmitter; b) a wireless receiver; c) fullbridge rectifier; d) pulse width modulator (PWM); e) two-channelanalog-to-digital converter (A/D); and f) a micro-controller unit (MCU):2. The apparatus in accordance with claim 1, wherein said wirelesstransmitter comprises: a) a wireless signal generation device whichgenerates a binary code, b) an antenna, c) and user selection means. 3.The wireless signal generation device which generates a binary code inaccordance with claim 2, wherein said wireless signal generation deviceis a five-function chip and wherein said binary code is a 5-bit binarycode.
 4. The apparatus in accordance with claim 2, wherein said userselection means are pushbuttons.
 5. The apparatus in accordance withclaim 1, wherein said model trains are DCC controlled.
 6. The apparatusin accordance with claim 1, wherein said model trains are AC poweredmodel trains driven by DC motors:
 7. The apparatus in accordance withclaim 1, wherein said model trains are DC powered model trains:
 8. Theapparatus in accordance with claim 1, wherein said MCU providesautomatic detection means wherein said means is selected from the groupconsisting of: model trains under DCC control, AC powered model trainsdriven by a DC motor, and DC powered model trains:
 9. The apparatus inaccordance with claim 1 wherein said MCU provides automatic detectionmeans wherein said means is selected from a group consisting of: modeltrains under DCC control, AC powered model trains driven by a DC motor,or DC powered trains:
 10. A method for providing a new controlcapability for DC model trains and for AC model trains driven by DCmotors; said method comprising the steps of: a) transmitting wirelesslya digital control function wherein a transmitter transmits to a functionreceiver; b) receiving a control signal via said wireless functionreceiver; c) feeding digital signals directly to the I/O port of themicrocontroller of the on-board sound unit; d) detecting and controllingsaid model trains using a micro-controller unit (MCU), wherein saiddigital control function provides an on-board function.
 11. The methodin accordance with claim 10, wherein said model trains are DCCcontrolled:
 12. The method defined by claim 10, wherein said modeltrains are AC powered model trains driven by DC motors:
 13. The methodin accordance with claim 10, wherein said model trains are DC poweredmodel trains.
 14. The method in accordance with claim 10, wherein saidMCU provides automatic detection means wherein said means is selectedfrom the group consisting of: model trains under DCC control, AC poweredmodel trains driven by a DC motor, and DC powered model trains:
 15. Themethod in accordance with claim 10, wherein said MCU provides automaticdetection means wherein said means is selected from the group consistingof; model trains under DCC control, AC powered model trains driven by aDC motor, and DC powered model trains:
 16. A system for providing a newcontrol capability for DC model trains and for AC model trains driven byDC motors, said system comprising: a) a wireless transmitter; b) atwo-channel analog-to-digital converter (A/D); c) a micro-controllerunit (MCU); d) a pulse width modulator (PWM); e) a wireless receiver;and f) a full bridge rectifier with filter which converts track power toDC to power the PWM circuit and microcontroller (MCU).
 17. The system inaccordance with claim 16, wherein said model trains are DCC controlled.18. The system in accordance with claim 16, wherein said model trainsare AC powered model trains driven by DC motors:
 19. The system inaccordance with claim 16, wherein said model trains are DC powered modeltrains.
 20. The system in accordance with claim 16, wherein said MCUprovides automatic detection means wherein said means is selected fromthe group consisting of: model trains under DCC control, AC poweredmodel trains driven by a DC motor, and DC powered model trains:
 21. Thesystem in accordance with claim 16, wherein said MCU provides automaticdetection means wherein said means is selected from the group consistingof: model trains under DCC control, AC powered model trains driven by aDC motor, and DC powered model trains:
 22. A program when executed on acomputer associated with the on-board sound module on model trainscauses the computer to perform the steps of: a) receiving a digitalcontrol signal; b) decoding said digital control signal; and c) usingsaid digital control signal, controlling on-board train functions; 23.The program in accordance with claim 22, wherein said model trains areDCC controlled.
 24. The program in accordance with claim 22, whereinsaid model trains are DC powered model trains:
 25. The program inaccordance with claim 22, wherein said model trains are AC powered modeltrains driven by DC motors:
 26. The program in accordance with claim 22,wherein said program provides automatic detection means wherein saidmeans is selected from the group consisting of: model trains under DCCcontrol, AC powered model trains driven by a DC motor, and DC poweredmodel trains:
 27. The program in accordance with claim 22, wherein saidprogram provides automatic detection means wherein said means isselected from the group consisting of: model trains under DCC control,AC powered model trains driven by a DC motor, and DC powered modeltrains.